Film formation apparatus and method for forming a film

ABSTRACT

An apparatus for forming a film having high uniformity in its film thickness distribution is provided. An evaporation source is used in which an evaporation cell, or a plurality of evaporation cells, having a longitudinal direction is formed, and by moving the evaporation source in a direction perpendicular to the longitudinal direction of the evaporation source, a thin film is deposited on a substrate. By making the evaporation source longer, the uniformity of the film thickness distribution in the longitudinal direction is increased. The evaporation source is moved, film formation is performed over the entire substrate, and therefore the uniformity of the film thickness distribution over the entire substrate can be increased.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to an apparatus or a method forforming a film used in manufacturing an EL (electroluminescence) elementhaving a structure composed of an anode, a cathode, and sandwichingbetween the anode and the cathode a light emitting material, inparticular a self-luminescing organic material (hereafter referred to asan organic EL material), from which EL (Electro Luminescence) isobtained.

[0003] 2. Description of the Related Art

[0004] There are two types of EL display devices, a passive (a simplematrix), and an active (an active matrix), and development of both isbeing enthusiastically performed. In particular, active matrix ELdisplay devices are in the spotlight at present. Furthermore, organicmaterials and inorganic materials exist for an EL material which becomesa light emitting layer of an EL element, and in addition organicmaterials are divided into low molecular weight (monomer) organic ELmaterials and high molecular weight (polymer) organic EL materials. Bothare being vigorously researched, but a film of a low molecular weightorganic EL material is mainly formed by evaporation, while a film of ahigh polymer organic EL material is mainly formed by application.

[0005] In order to manufacture a color display EL display device, it isnecessary to form films of EL materials which emit different colors, foreach pixel. However, in general EL materials are weak with respect towater and oxygen, and patterning by photolithography cannot beperformed. It is therefore necessary to form the films at the same timeas patterning.

[0006] The most general method is a method for forming a mask, made froma metallic plate or a glass plate and having an open portion formed init, between the substrate onto which a film is formed and an evaporationsource. In this case, the vaporized EL material from the evaporationsource passes through only the open portion to thereby form the filmselectively, and therefore it is possible to form an EL layer in whichfilm formation and patterning are performed simultaneously.

[0007] With a conventional evaporation apparatus, the EL material whichflies off in a radial shape from one evaporation source accumulates on asubstrate, forming a thin film, and therefore, considering the distancethat the EL material covers, a way of substrate positioning was devised.For example, a method of fixing a substrate to a circular cone shapedsubstrate holder, making the distances from the evaporation source tothe substrate all equal, is performed.

[0008] However, when employing a multi-beveling process in which aplurality of panels are manufactured on a large size substrate, thesubstrate holder becomes extremely large if the above stated process isperformed, and this leads to the main body of the film formationapparatus becoming large. Further, the substrate is planar whenperforming by single wafer processing as well, and therefore thedistances from the evaporation source differs within the surface of thesubstrate, and a problem remains in that it is difficult to deposit at auniform film thickness.

[0009] In addition, if the distance between the evaporation source andthe shadow mask is not made longer when using a large size substrate,the vaporized EL material does not sufficiently spread, and it becomesdifficult to form a uniform thin film over the entire substrate surface.Maintaining this distance also encourages making the apparatus largesize.

SUMMARY OF THE INVENTION

[0010] The present invention is made in view of the above statedproblems, and an object of the present invention is to provide a filmformation apparatus capable of forming a thin film having a highlyuniform film thickness distribution at high throughput. Further, anobject of the present invention is to provide a method of forming a filmusing the film formation apparatus of the present invention.

[0011] An evaporation source in which an evaporation cell having alongitudinal direction (a portion in which a thin film material forevaporation is placed), or a plurality of the evaporation cells, areformed is used in the present invention. By moving the evaporationsource in a direction perpendicular to the longitudinal direction of theevaporation source, a thin film is formed. Note that, “having alongitudinal direction” indicates a long and thin rectangular shape, along and thin elliptical shape, or a linear shape. It is preferable thatthe length in the longitudinal direction be longer than the length ofone side of a substrate for the present invention because processing canbe performed in one sweep. Specifically, the length may be from 300 mmto 1200 mm (typically between 600 and 800 mm).

[0012] The positional relationship between the evaporation source of thepresent invention and the substrate is shown in FIGS. 1A to 1c. FIG. 1Ais a top view, FIG. 1B is a cross sectional diagram of FIG. 1A cut alongthe line segment A-A′, and FIG. 1C is a cross sectional diagram of FIG.1A cut along the line segment B-B′. Note that, common symbols are usedin FIGS. 1A to 1C.

[0013] As shown in FIG. 1A, a shadow mask 102 is placed below asubstrate 101, and in addition, a rectangular shaped evaporation source104, in which a plurality of evaporation cells 103 are lined up on astraight line, is placed below the shadow mask 102. Note that,throughout this specification, the term substrate includes a substrateand thin films formed on that substrate. Further, the term substratesurface indicates the substrate surface on which the thin films areformed.

[0014] The length of the longitudinal direction of the evaporationsource 104 is longer than the length of one side of the substrate 101,and a mechanism for moving the evaporation source 104 in a directionshown by an arrow (a direction perpendicular to the longitudinaldirection of the evaporation source 104) is prepared. By then moving theevaporation source 104, a thin film can be formed over the entiresurface of the substrate. Note that, when the length of the longitudinaldirection is shorter than that of one side of the substrate, the thinfilm may be formed by repeating a plurality of scans. Furthermore, alamination of the same thin film may be formed by repeatedly moving theevaporation source 104.

[0015] The thin film material vaporized by each of the evaporation cells103 is scattered in the upward direction, passes through open portions(not shown in the figures) formed in the shadow mask 102, andaccumulates on the substrate 101. The thin film is thus selectivelydeposited on the substrate 101. A region in which the thin film materialscattered from one evaporation cell 103 forms a film overlaps with aregion in which the thin film material scattered from an adjoiningevaporation cell 103 forms a film. By mutually overlapping the regionsin which the film is deposited, the film is formed in a rectangularshape region.

[0016] The uniformity in film thickness of a thin film can thus begreatly improved with the present invention by using the evaporationsource having a plurality of evaporation cells lined up, and byirradiating from a line instead of conventional irradiation from apoint. In addition, by moving the rectangular shape evaporation sourcebelow the substrate surface, film formation can be performed at highthroughput.

[0017] Additionally, it is not necessary to make the distance betweenthe evaporation source 104 and the shadow mask 102 longer with thepresent invention, and evaporation can be performed in a state ofextreme closeness. This is because a plurality of evaporation cells areformed in alignment, and even if the scattering distance of the thinfilm material is short, film formation can be performed simultaneouslyfrom the central portion to the edge portion of the substrate. Thiseffect is greater the higher the density at which the evaporation cells103 are lined up.

[0018] The distance from the evaporation source 104 to the shadow mask102 is not particularly limited because it differs depending upon thedensity at which the evaporation cells 103 are formed. However, if it istoo close, then it becomes difficult to form a uniform film from thecenter portion to the edge portion, and if it is too far, there will beno change from conventional evaporation by irradiating from a point.Therefore, if the gap between evaporation cells 103 is taken as “a”, itis preferable to make the distance between the evaporation source 104and the shadow mask 102 from 2 a to 10 a (more preferably from 5 a to 50a).

[0019] With the film formation apparatus of the present inventionstructured as above, uniformity of the distribution of film thickness ofa thin film in a rectangular shape, elliptical shape, or a linear shaperegion is maintained by using the evaporation source, and by moving theevaporation source on top of that region, it becomes possible to form athin film having high uniformity over the entire surface of thesubstrate. Further, this is not evaporation from a point, and thereforethe distance between the evaporation source and the substrate can bemade shorter, and the uniformity of film thickness can be furtherincreased.

[0020] Furthermore, it is effective to add means for generating a plasmawithin a chamber in the film formation apparatus of the presentinvention. By performing a plasma process in accordance with oxygen gasor a plasma process in accordance with a gas containing fluorine, thinfilms deposited on the chamber walls are removed, and cleaning of theinside of the chamber can be performed. Parallel-plate electrodes may beformed within the chamber, and a plasma may be generated between theplates as the means for generating the plasma.

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In the accompanying drawings:

[0022]FIGS. 1A to 1C are diagrams showing a structure of an evaporationsource;

[0023]FIGS. 2A and 2B are diagrams showing a structure of an evaporationchamber;

[0024]FIG. 3 is a diagram showing a structure of an evaporation chamber;

[0025]FIG. 4 is a diagram showing a structure of a film formationapparatus;

[0026]FIG. 5 is a diagram showing a structure of a film formationapparatus;

[0027]FIG. 6 is a diagram showing a structure of a film formationapparatus;

[0028]FIG. 7 is a diagram showing a structure of a film formationapparatus; and

[0029]FIG. 8 is a diagram showing a structure of a film formationapparatus.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] Embodiment mode

[0031] A structure of an evaporation chamber prepared in a filmformation apparatus of the present invention is shown in FIGS. 2A and2B. FIG. 2A is a top view of the evaporation chamber, and FIG. 2B is across sectional diagram. Note that common symbols are used for commonportions. Further, an example of forming an EL (electroluminescence)film as a thin film is shown in the embodiment mode.

[0032] In FIG. 2A, reference numeral 201 denotes a chamber, andreference numeral 202 denotes a substrate conveyor opening, from which asubstrate is conveyed to the inside portion of the chamber 201. Aconveyed substrate 203 is set in a substrate holder 204, and is conveyedin to a film formation portion 206 by a conveyor rail 205 a, as shown byan arrow 205 b.

[0033] When the substrate 203 is conveyed to a film formation portion206, a shadow mask 208 fixed to a mask holder 207 approaches thesubstrate 203. Note that, a metallic plate is used as the material ofthe shadow mask 208 in this embodiment mode. (See FIG. 2B) Further, openportions 209 are formed having a rectangular shape, elliptical shape, orlinear shape in the shadow mask 208 in this embodiment mode. The shapeof the opening portions is not limited, of course, and a matrix shape ora net shape may also be formed.

[0034] At this point in the embodiment mode, this is a structure inwhich an electromagnet 210 approaches the substrate 203, as shown inFIG. 2B. When a magnetic field is formed by the electromagnet 210, theshadow mask 208 is drawn to the substrate 203, and is maintained at apredetermined gap. This gap is secured by a plurality of projections 301formed in the shadow mask 208, as shown in FIG. 3.

[0035] This type of structure is particularly effective when thesubstrate 203 is a large size substrate exceeding 300 mm. If thesubstrate 203 is large size, then deflection (warp) is generated by theweight of the substrate itself. However, the substrate 203 can also bepulled toward the electromagnet 210 and the flexure can be canceledprovided that the shadow mask 208 is drawn toward the substrate 203 sideby the electromagnet 210. Note that, as shown in FIG. 4, it ispreferable to form projections 401 in the electromagnet 210, and tomaintain a gap between the substrate 203 and the electromagnet 210.

[0036] When the gap between the substrate 203 and the shadow mask 208 issecured, an evaporation source 212, on which evaporation cells 211having a longitudinal direction are formed, is then moved in thedirection of the arrow 213. An EL material formed in the inside portionof the evaporation cells is vaporized by being heated while being moved,and is scattered within the chamber of the film formation portion 206.Note that the distance between the evaporation source 212 and thesubstrate 203 can be made extremely short for the case of the presentinvention, and therefore adhesion of the EL material to a drive portion(a portion for driving the evaporation source, the substrate holder, orthe mask holder) within the chamber can be minimized.

[0037] The evaporation source 212 is scanned from one end of thesubstrate 203 to the other end. As shown in FIG. 2A, the length of thelongitudinal direction of the evaporation source 212 is sufficientlylong in the embodiment mode, and therefore it can be moved over theentire surface of the substrate 203 by scanning once.

[0038] After a film is formed from a red, green, or blue color ELmaterial (red here) as above, the magnetic field of the electromagnet210 is switched off, the mask holder 207 is dropped down, and thedistance between the shadow mask 208 and the substrate 203 increases.The substrate holder 204 is then shifted over by one pixel portion, themask holder 207 is raised again, and the shadow mask 208 and thesubstrate 203 are made to come closer. In addition, a magnetic field isformed by the electromagnet 210, and deflection (warp) of the shadowmask 208 and the substrate 203 is eliminated. The evaporation cell ischanged next, and film formation of a red, green, or blue EL material(green here) is performed.

[0039] Note that, a structure in which the substrate holder 204 isshifted by one pixel portion is shown here, but the mask holder 204 mayalso be shifted by one pixel portion.

[0040] After all film formation of red, green, and blue EL materials bythis type of repetition, the substrate 203 is lastly conveyed to thesubstrate conveyor opening 202, and is removed from the chamber 201 by arobot arm (not shown in the figures). Film formation of the EL filmsusing the present invention is thus completed.

[0041] Embodiment 1

[0042] An explanation of a film formation apparatus of the presentinvention is explained using FIG. 5. In FIG. 5, reference numeral 501denotes a conveyor chamber. A conveyor mechanism 502 is prepared in theconveyor chamber 501, and conveyance of a substrate 503 is performed.The conveyor chamber 501 has a reduced pressure atmosphere, and isconnected to each processing chamber by a gate. Delivery of thesubstrate to each processing chamber is performed by the conveyormechanism 502 when the gates are open. Further, it is possible to use anevacuation pump such as an oil-sealed rotary pump, a mechanical boosterpump, a turbo-molecular pump, and a cryo-pump in lowering the pressureof the conveyor chamber 501, but a cryo-pump, which is effective inremoving moisture, is preferable.

[0043] An explanation regarding each processing chamber is made below.Note that the conveyor chamber 501 has a reduced pressure atmosphere,and therefore an evacuation pump (not shown in the figure) is preparedin each processing chamber directly connected to the conveyor chamber501. The above stated oil-sealed rotary pump, mechanical booster pump,turbo-molecular pump, and cryo-pump are used as the evacuation pump.

[0044] First, reference numeral 504 denotes a load chamber forperforming substrate setting, and it is also an unload chamber. The loadchamber 504 is connected to the conveyor chamber 501 by a gate 500 a,and a carrier (not shown in the figure) on which the substrate 503 isset is arranged here. Note that the load chamber 504 may also beseparated into a substrate loading chamber and a substrate unloadingchamber. Further, the above evacuation pump and a purge line forintroducing high purity nitrogen gas or noble gas are prepared for theload chamber 504.

[0045] Note that a substrate on which process through the formation of atransparent conducting film, which becomes an anode of an EL element hasbeen conducted, is used as the substrate 503 in Embodiment 1. Thesubstrate 503 is set in the carrier with the surface on which the filmsare formed facing downward. This is in order to make a face-down method(also referred to as a deposition-up method) easier to perform whenlater performing film formation by evaporation. The face down methoddenotes a method in which film formation is performed with the substratesurface onto which a film is to be formed facing downward, and adhesionof refuse (dirt) or the like can be suppressed by this method.

[0046] Next, reference numeral 505 denotes a processing chamber forprocessing a surface of an anode or a cathode of an EL element (inEmbodiment 1, an anode), and the processing chamber 505 is connected tothe conveyor chamber 501 by a gate 500 b. The processing chamber can bechanged variously depending upon the manufacturing process of the ELelement, and in Embodiment 1 heat treatment of the surface of the anodemade from the transparent conducting film can be performed at between100 and 120° C. in oxygen while irradiating ultraviolet light. This typeof preprocess is effective when processing the anode surface of the ELelement.

[0047] Next, reference numeral 506 denotes an evaporation chamber forfilm deposition of an organic EL material by evaporation, and isreferred to as an evaporation chamber (A). The evaporation chamber (A)506 is connected to the conveyor chamber 501 through a gate 500 c. InEmbodiment 1 an evaporation chamber having the structure shown in FIGS.2A and 2B is used as the evaporation chamber (A) 506.

[0048] In a film formation portion 507 of the evaporation chamber (A)506, first a hole injecting layer is deposited over the entire substratesurface, then a light emitting layer for emitting red color light isformed, next a light emitting layer for emitting green color light isformed, and lastly a light emitting layer for emitting blue color lightis formed. Note that any known materials may be used as the holeinjecting layer, the red color light emitting layer, the green colorlight emitting layer, and the blue color light emitting layer.

[0049] The evaporation chamber (A) 506 has a structure which is capableof switching in correspondence with the type of organic material of thefilm formation evaporation source. Namely, a preparation chamber 508 forstoring a plurality of types of evaporation sources is connected to theevaporation chamber (A) 506, and evaporation source switching isperformed by an internal conveyor mechanism. The evaporation sourcetherefore changes when the organic EL material for film formationchanges. Further, the same mask of shadow mask is moved by one pixelportion whenever the organic EL material for film formation is switched.

[0050] Note that FIGS. 2A and 2B may be referred to regarding filmformation processes occurring within the evaporation chamber (A) 506.

[0051] Next, reference numeral 509 denotes an evaporation chamber forfilm formation of a conducting film (a metallic film which becomes acathode is used in Embodiment 1), which becomes an anode or a cathode ofthe EL element, by evaporation, and is referred to as an evaporationchamber (B). The evaporation chamber (B) 509 is connected to theconveyor chamber 501 through a gate 500 d. An evaporation chamber havingthe structure shown in FIGS. 2A and 2B is used as the evaporationchamber (B) 509 in Embodiment 1. In a film formation portion 510 withinthe evaporation chamber (B) 509, an Al-Li alloy film (an alloy film ofaluminum and lithium) is deposited as the conducting film which becomesthe EL element cathode.

[0052] Note that it is also possible to co-evaporate an element residingin group 1 or group 2 of the periodic table, and aluminum.Co-evaporation refers to evaporation in which cells are heated at thesame time, and different materials are combined at the stage of filmformation.

[0053] Next, reference numeral 511 denotes a sealing chamber (alsoreferred to as an enclosing chamber or a globe box), and is connected tothe load chamber 504 through a gate 500 e. A process for final hermeticsealing of the EL element is performed in the sealing chamber 511. Thisprocess is one in which the formed EL element is protected from oxygenand moisture, and a means for mechanically sealing by a sealingmaterial, or a means for sealing by a thermally hardened resin or anultraviolet light hardened resin is used.

[0054] Glass, ceramic, plastic, and metal can be used as the sealingmaterial, but when light is irradiated onto the sealing material side,the material must have transparency. Further, when the sealing materialand substrate on which the above EL element is formed are joined using athermal hardened resin or an ultraviolet light hardened resin, the resinis hardened by heat treatment or by ultraviolet light irradiationprocessing, forming an airtight space. It is also effective to form adrying agent, typically barium oxide, within the airtight space.

[0055] Further, it is also possible to fill the space between thesealing material and the substrate on which the EL element is formed bya thermal hardened resin or an ultraviolet light hardened resin. In thiscase, it is effective to add a drying agent, typically barium oxide,within the thermal hardened resin or the ultraviolet light hardenedresin.

[0056] A mechanism for irradiating ultraviolet light (hereafter referredto as an ultraviolet light irradiation mechanism) 512 is formed on aninternal portion of the sealing chamber 511, and the film formationapparatus shown in FIG. 5 has a structure in which an ultraviolet lighthardened resin is hardened by ultraviolet light emitted from theultraviolet light irradiation mechanism 512. Further, it is possible toreduce the pressure of the inside portion of the sealing chamber 511 byattaching an evacuation pump. When mechanically performing the abovesealing processes by using robot operation, oxygen and moisture can beprevented from mixing in by performing the processes under reducedpressure. Furthermore, it is also possible to pressurize the insideportion of the sealing chamber 511. In this case pressurization isperformed by a high purity nitrogen gas or noble gas while purging, andan incursion of a contaminant such as oxygen from the atmosphere isprevented.

[0057] Next, a delivery chamber (a pass box) 513 is connected to thesealing chamber 511. A conveyor mechanism (B) 514 is formed in thedelivery chamber 513, and the substrate on which the EL element has beencompletely sealed in the sealing chamber 511 is conveyed to the deliverychamber 513. It is possible to also make the delivery chamber 513reduced pressure by attaching an evacuation pump. The delivery chamber513 is equipment used so that the sealing chamber 511 is not directlyexposed to the atmosphere, and the substrate is removed from here.

[0058] It thus becomes possible to manufacture an EL display devicehaving high reliability by using the film formation apparatus shown inFIG. 5 because processing can be finished up through the point, withoutexposure to the atmosphere, at which the EL element is completely sealedinto an airtight space.

[0059] Embodiment 2

[0060] A case of using a film formation apparatus of the presentinvention in a multi-chamber method (also referred to as a cluster toolmethod) is explained using FIG. 6. Reference numeral 601 denotes aconveyor chamber in FIG. 6. A conveyor mechanism (A) 602 is prepared inthe conveyor chamber 601, and conveyance of a substrate 603 isperformed. The conveyor chamber 601 has a reduced pressure atmosphere,and is connected to each processing chamber by a gate. Delivery of thesubstrate to each processing chamber is performed by the conveyormechanism (A) 602 when the gates are open. Further, it is possible touse an evacuation pump such as an oil-sealed rotary pump, a mechanicalbooster pump, a turbo-molecular pump, and a cryo-pump in lowering thepressure of the conveyor chamber 601, but a cryo-pump, which iseffective in removing moisture, is preferable.

[0061] An explanation regarding each processing chamber is made below.Note that the conveyor chamber 601 has a reduced pressure atmosphere,and therefore an evacuation pump (not shown in the figure) is preparedin each processing chamber directly connected to the conveyor chamber601. The above stated oil-sealed rotary pump, mechanical booster pump,turbo-molecular pump, and cryo-pump is used as the evacuation pump.

[0062] First, reference numeral 604 denotes a load chamber forperforming substrate setting, and it is also called an unload chamber.The load chamber 604 is connected to the conveyor chamber 601 by a gate600 a, and a carrier (not shown in the figure) on which the substrate603 is set is arranged here. Note that the load chamber 604 may also beseparated into a substrate loading chamber and a substrate unloadingchamber. Further, the above evacuation pump and a purge line forintroducing high purity nitrogen gas or noble gas are prepared for theload chamber 604.

[0063] Next, reference numeral 605 denotes a preprocessing chamber forprocessing a surface of an anode or a cathode of an EL element (inEmbodiment 2, an anode), and the processing chamber 605 is connected tothe conveyor chamber 601 by a gate 600 b. The preprocessing chamber canbe changed variously depending upon the manufacturing process of the ELelement, and in Embodiment 2 heat treatment of the surface of the anodemade from the transparent conducting film can be performed at between100 and 120° C. in oxygen while irradiating ultraviolet light. This typeof preprocess is effective when processing the anode surface of the ELelement.

[0064] Next, reference numeral 606 denotes an evaporation chamber forfilm deposition of an organic EL material by evaporation, and isreferred to as an evaporation chamber (A). The evaporation chamber (A)606 is connected to the conveyor chamber 601 through a gate 600 c. InEmbodiment 2 an evaporation chamber having the structure shown in FIGS.2A and 2B is used as the evaporation chamber (A) 606.

[0065] In a film formation portion 607 of the evaporation chamber (A)606, a hole injecting layer is first deposited over the entire substratesurface, then a light emitting layer for emitting red color light isformed. Accordingly, an evaporation source and a shadow mask areprovided with two types of each corresponding to the organic material tobe the hole injecting layer and the red light emitting layer, and arestructured to be capable of switching. Note that known materials may beused as the hole injecting layer, and the red color light emittinglayer.

[0066] Next, reference numeral 608 denotes an evaporation chamber forfilm formation of an organic EL material by evaporation, and is referredto as an evaporation chamber (B). The evaporation chamber (B) 608 isconnected to the conveyor chamber 601 through a gate 600 d. InEmbodiment 2, an evaporation chamber with the structure shown in FIGS.2A and 2B is used as the evaporation chamber (B) 608. A light emittinglayer for emitting green color light is deposited in a film formationportion 609 within the evaporation chamber (B) 608 in Embodiment 2. Notethat a known material may be used as the light emitting layer foremitting green color light in Embodiment 2.

[0067] Next, reference numeral 610 denotes an evaporation chamber forfilm formation of an organic EL material by evaporation, and is referredto as an evaporation chamber (C). The evaporation chamber (C) 610 isconnected to the conveyor chamber 601 through a gate 600 e. InEmbodiment 2, an evaporation chamber with the structure shown in FIGS.2A and 2B is used as the evaporation chamber (C) 610. A light emittinglayer for emitting blue color light is deposited in a film formationportion 611 within the evaporation chamber (C) 610 in Embodiment 2. Notethat a known material may be used as the light emitting layer foremitting blue color light in Embodiment 2.

[0068] Next, reference numeral 612 denotes an evaporation chamber forfilm formation of a conducting film, which becomes an anode or a cathodeof the EL element, by evaporation (a metallic film which becomes acathode is used in Embodiment 2), and is referred to as an evaporationchamber (D). The evaporation chamber (D) 612 is connected to theconveyor chamber 601 through a gate 600 f. An evaporation chamber havingthe structure shown in FIGS. 2A and 2B is used as the evaporationchamber (D) 612 in Embodiment 2. In a film formation portion 613 withinthe evaporation chamber (D) 612, an Al-Li alloy film (an alloy film ofaluminum and lithium) is deposited as the conducting film which becomesthe EL element cathode. Note that it is also possible to co-evaporate anelement residing in group 1 or group 2 of the periodic table, andaluminum.

[0069] Next, reference numeral 614 denotes a sealing chamber, and isconnected to the load chamber 604 through a gate 600 g. For explanationof the sealing chamber 614 refer to Embodiment 1. Further, anultraviolet light irradiation mechanism 615 is formed in the insideportion of the sealing chamber 614, similar to Embodiment 1. Inaddition, a delivery chamber 616 is connected to the sealing chamber615. A conveyor mechanism (B) 617 is formed in the delivery chamber 616,and the substrate, on which the EL element has been completely sealed inthe sealing chamber 614, is conveyed to the delivery chamber 616.Embodiment 1 may be referred to for an explanation of the deliverychamber 616.

[0070] It thus becomes possible to manufacture an EL display devicehaving high reliability by using the film formation apparatus shown inFIG. 6 because processing can be finished up through the point, withoutexposure to the atmosphere, at which the EL element is completely sealedinto an airtight space.

[0071] Embodiment 3

[0072] A case of using a film formation apparatus of the presentinvention in an in-line method is explained using FIG. 7. Referencenumeral 701 denotes a load chamber in FIG. 7, and conveyance of asubstrate is performed here. An evacuation system 700 a is prepared inthe load chamber 701, and the evacuation system 700 a has a structurecontaining a first valve 71, a turbo-molecular pump 72, a second valve73, and a rotary pump (oil-sealed rotary pump) 74.

[0073] The first valve 71 is a main valve, and there are cases when italso combines a conductance valve, and there are also cases when abutterfly valve is used. The second valve 73 is a fore valve, and thesecond valve 73 is opened first, and the load chamber 701 is roughlyreduced in pressure by the rotary pump 74. The first valve 71 is openednext, and the pressure is reduced by the turbo-molecular pump 72 until ahigh vacuum is reached. Note that it is possible to use a mechanicalbooster pump or a cryo-pump as a substitute for the turbo-molecularpump, but the cryo-pump is particularly effective in removing moisture.

[0074] Next, reference numeral 702 denotes a preprocessing chamber forprocessing a surface of an anode or a cathode of an EL element (inEmbodiment 3, an anode), and the preprocessing chamber 702 is preparedwith an evacuation system 700 b. Further, it is hermetically sealed offfrom the load chamber 701 by a gate not shown in the figure. Thepreprocessing chamber 702 can be changed variously depending upon themanufacturing process of the EL element, and in Embodiment 3 heattreatment of the surface of the anode made from the transparentconducting film can be performed at between 100 and 120° C. in oxygenwhile irradiating ultraviolet light.

[0075] Next, reference numeral 703 denotes an evaporation chamber forfilm deposition of an organic EL material by evaporation, and isreferred to as an evaporation chamber (A). Further, it is hermeticallysealed off from the load chamber 702 by a gate not shown in the figure.The evaporation chamber (A) 703 is prepared with an evacuation system700 c. In Embodiment 3 an evaporation chamber having the structure shownin FIGS. 2A and 2B is used as the evaporation chamber (A) 703.

[0076] A substrate 704 conveyed to the evaporation chamber (A) 703, andan evaporation source 705 prepared in the evaporation chamber (A) 703,are moved in the direction of the arrows, respectively, and filmformation is performed. Note that FIGS. 2A and 2B may be referred toregarding detailed operation of the evaporation chamber (A) 703. A holeinjecting layer is deposited in the evaporation chamber (A) 703 inEmbodiment 3. A known material may be used as the hole injecting layer.

[0077] Next, reference numeral 706 denotes an evaporation chamber forfilm formation of an organic EL material by evaporation, and is referredto as an evaporation chamber (B). The evaporation chamber (B) 706 isprepared with an evacuation system 700 d. Further, it is hermeticallysealed off from the evacuation chamber (A) 703 by a gate not shown inthe figure. An evaporation chamber having the structure shown in FIGS.2A and 2B is formed as the evaporation chamber (B) 706 in Embodiment 3.The explanation of FIGS. 2A and 2B may therefore be referred toregarding detailed operation of the evaporation chamber (B) 706.Further, a light emitting layer for emitting red color light isdeposited in the evaporation chamber (B) 706. A known material may beused as the light emitting layer which emits red color light.

[0078] Next, reference numeral 707 denotes an evaporation chamber forfilm formation of an organic EL material by evaporation, and is referredto as an evaporation chamber (C). The evaporation chamber (C) 707 isprepared with an evacuation system 700 e. Further, it is hermeticallysealed off from the evacuation chamber (B) 706 by a gate not shown inthe figure. An evaporation chamber having the structure shown in FIGS.2A and 2B is formed as the evaporation chamber (C) 707 in Embodiment 3.The explanation of FIGS. 2A and 2B may therefore be referred toregarding detailed operation of the evaporation chamber (C) 707.Further, a light emitting layer for emitting green color light isdeposited in the evaporation chamber (C) 707. A known material may beused as the light emitting layer which emits green color light.

[0079] Next, reference numeral 708 denotes an evaporation chamber forfilm formation of an organic EL element by evaporation, and is referredto as an evaporation chamber (D). The evaporation chamber (D) 708 isprepared with an evacuation system 700 f. Further, it is hermeticallysealed off from the evacuation chamber (C) 707 by a gate not shown inthe figure. An evaporation chamber having the structure shown in FIGS.2A and 2B is formed as the evaporation chamber (D) 708 in Embodiment 3.The explanation of FIGS. 2A and 2B may therefore be referred toregarding detailed operation of the evaporation chamber (D) 708.Further, a light emitting layer for emitting blue color light isdeposited in the evaporation chamber (D) 708. A known material may beused as the light emitting layer which emits blue color light.

[0080] Next, reference numeral 709 denotes an evaporation chamber forfilm formation of a conducting film (a metallic film which becomes acathode is used in Embodiment 3), which becomes an anode or a cathode ofthe EL element, by evaporation, and is referred to as an evaporationchamber (E). The evaporation chamber (E) 709 is prepared with anevacuation system 700 g. Further, it is hermetically sealed off from theevacuation chamber (D) 708 by a gate not shown in the figure. Anevaporation chamber having the structure shown in FIGS. 2A and 2B isformed as the evaporation chamber (E) 709 in Embodiment 3. Theexplanation of FIGS. 2A and 2B may therefore be referred to regardingdetailed operation of the evaporation chamber (E) 709.

[0081] An Al-Li alloy film (an alloy film of aluminum and lithium) isdeposited in the evaporation chamber (E) 709 as the conducting filmwhich becomes the EL element cathode. Note that it is also possible toco-evaporate an element residing in group 1 or group 2 of the periodictable, and aluminum.

[0082] Next, reference numeral 710 denotes a sealing chamber, and it isprepared with an evacuation system 700 h. Further, it is hermeticallysealed off from the evacuation chamber (E) 709 by a gate not shown inthe figure. Embodiment 1 may be referred to regarding an explanation ofthe sealing chamber 710. Furthermore, an ultraviolet light irradiationmechanism is provided on the inside portion of the sealing chamber 710,similar to Embodiment 1.

[0083] Finally, reference numeral 711 denotes an unload chamber, and itis prepared with an evacuation system 700 i. The substrate on which theEL element is formed is removed from here.

[0084] It thus becomes possible to manufacture an EL display devicehaving high reliability by using the film formation apparatus shown inFIG. 7 because processing can be finished up through the point, withoutexposure to the atmosphere, at which the EL element is completely sealedinto an airtight space. An EL display device can furthermore bemanufactured at a high throughput in accordance with the in-line method.

[0085] Embodiment 4

[0086] A case of using a film formation apparatus of the presentinvention in an in-line method is explained using FIG. 8. Referencenumeral 801 denotes a load chamber in FIG. 8, and conveyance of asubstrate is performed here. An evacuation system 800 a is prepared inthe load chamber 801, and the evacuation system 800 a has a structurecontaining a first valve 81, a turbo-molecular pump 82, a second valve83, and a rotary pump (oil-sealed rotary pump) 84.

[0087] Next, reference numeral 802 denotes a preprocessing chamber forprocessing a surface of an anode or a cathode of an EL element (inEmbodiment 4, an anode), and the preprocessing chamber 802 is preparedwith an evacuation system 800 b. Further, it is hermetically sealed offfrom the load chamber 801 by a gate not shown in the figure. Thepreprocessing chamber 802 can be changed variously depending upon themanufacturing process of the EL element, and in Embodiment 4 heattreatment of the surface of the anode made from the transparentconducting film can be performed at between 100 and 120° C. in oxygenwhile irradiating ultraviolet light.

[0088] Next, reference numeral 803 denotes an evaporation chamber forfilm deposition of an organic EL material by evaporation, and theevaporation chamber 803 is prepared with an evacuation system 800 c. InEmbodiment 4 an evaporation chamber having the structure shown in FIGS.2A and 2B is used as the evaporation chamber 803. A substrate 804conveyed to the evaporation chamber 803, and an evaporation source 805prepared in the evaporation chamber 803, are moved in the direction ofthe arrows, respectively, and film formation is performed.

[0089] In Embodiment 4, it is preferable to switch the evaporationsource 803 or the shadow mask (not shown) at the time of film depositionin the evaporation chamber 803 in order to form a conductive film to behole injection layer, a red light emitting layer, a green light emittinglayer, a blue light emitting layer or a cathode. In Embodiment 4, theevaporation chamber 803 is connected with a reserve chamber 806, inwhich the evaporation source and the shadow mask are stored to switchappropriately.

[0090] Next, reference numeral 807 denotes a sealing chamber, and it isprepared with an evacuation system 800 d. Further, it is hermeticallysealed off from the evacuation chamber 803 by a gate not shown in thefigure. Embodiment 1 may be referred to regarding an explanation of thesealing chamber 807. Furthermore, an ultraviolet light irradiationmechanism (not shown in the figure) is provided on the inside portion ofthe sealing chamber 807, similar to Embodiment 1.

[0091] Finally, reference numeral 808 denotes an unload chamber, and itis prepared with an evacuation system 800 e. The substrate on which theEL element is formed is removed from here.

[0092] It thus becomes possible to manufacture an EL display devicehaving high reliability by using the film formation apparatus shown inFIG. 8 because processing can be finished up through to the point, atwhich the EL element is completely sealed into an airtight space withoutexposure to the atmosphere. An EL display device can furthermore bemanufactured at a high throughput in accordance with the in-line method.

[0093] By using the film formation apparatus of the present invention,it becomes possible to perform film formation, at high throughput, of athin film having high uniformity in its film thickness distribution onthe substrate surface.

What is claimed is:
 1. A film formation apparatus comprising: anevaporation source having a longitudinal direction; and a mechanism formoving the evaporation source in a direction perpendicular to thelongitudinal direction of the evaporation source.
 2. An apparatusaccording to claim 1 , wherein the evaporation source is provided withan evaporation cell having a longitudinal direction.
 3. An apparatusaccording to claim 1 , wherein the evaporation source is provided with aplurality of evaporation cells.
 4. A film formation apparatuscomprising: an evaporation source having a longitudinal direction; amechanism for moving the evaporation source in a direction perpendicularto the longitudinal direction of the evaporation source; and anelectromagnet formed over top of the mechanism.
 5. An apparatusaccording to claim 4 , wherein the evaporation source is provided withan evaporation cell having a longitudinal direction.
 6. An apparatusaccording to claim 4 , wherein the evaporation source is provided with aplurality of evaporation cells.
 7. A film formation apparatuscomprising: a load chamber; a conveyor chamber connected to the loadchamber; and an evaporation chamber connected to the conveyor chamber,wherein the evaporation chamber contains an evaporation source having alongitudinal direction, and a mechanism for moving the evaporationsource in a direction perpendicular to the longitudinal direction of theevaporation source.
 8. An apparatus according to claim 7 , wherein theevaporation source is provided with an evaporation cell having alongitudinal direction.
 9. An apparatus according to claim 7 , whereinthe evaporation source is provided with a plurality of evaporationcells.
 10. A film formation apparatus comprising: a load chamber; aconveyor chamber connected to the load chamber; and an evaporationchamber connected to the conveyor chamber, wherein the evaporationchamber contains an evaporation source having a longitudinal direction,and a mechanism for moving the evaporation source in a directionperpendicular to the longitudinal direction of the evaporation source,and an electromagnet formed over top of the mechanism.
 11. An apparatusaccording to claim 10 , wherein the evaporation source is provided withan evaporation cell having a longitudinal direction.
 12. An apparatusaccording to claim 10 , wherein the evaporation source is provided witha plurality of evaporation cells.
 13. A film formation apparatuscomprising: a load chamber; an unload chamber; and an evaporationchamber, wherein said load chamber and said unload chamber and saidevaporation chamber are connected in series, and wherein the evaporationchamber contains an evaporation source having a longitudinal direction,and a mechanism for moving the evaporation source in a directionperpendicular to the longitudinal direction of the evaporation source.14. An apparatus according to claim 13 , wherein the evaporation sourceis provided with an evaporation cell having a longitudinal direction.15. An apparatus according to claim 13 , wherein the evaporation sourceis provided with a plurality of evaporation cells.
 16. A film formationapparatus comprising: a load chamber; an unload chamber; and anevaporation chamber, wherein said load chamber and said unload chamberand said evaporation chamber are connected in series, and wherein theevaporation chamber contains an evaporation source having a longitudinaldirection, and a mechanism for moving the evaporation source in adirection perpendicular to the longitudinal direction of the evaporationsource, and an electromagnet formed over top of the mechanism.
 17. Anapparatus according to claim 16 , wherein the evaporation source isprovided with an evaporation cell having a longitudinal direction. 18.An apparatus according to claim 16 , wherein the evaporation source isprovided with a plurality of evaporation cells.
 19. A method of forminga thin film over a substrate while moving an evaporation source, havinga longitudinal direction, in a direction perpendicular to thelongitudinal direction of the evaporation source.
 20. A method offorming a thin film over a substrate while moving an evaporation source,having a longitudinal direction, in a direction perpendicular to thelongitudinal direction of the evaporation source, wherein the substrateand a shadow mask composed of a metal are in a state of contact inaccordance with an electromagnet.